Distance calculation device

ABSTRACT

Provided is a distance calculating apparatus calculating a real distance from a map distance of a map path connecting a first point and a second point on a map, the apparatus including: a housing; a scale input unit into which a reduced scale is input, disposed in the housing; an optical sensor unit disposed in the housing, the optical sensor unit sensing movement of the housing using light and outputting an electrical signal when the housing is moved along the map path; a calculation unit disposed in the housing, the calculation unit calculating the map distance using the electrical signal input from the optical sensor unit and calculating the real distance using the map distance and the reduced scale input from the scale input unit; and a display unit disposed in the housing, the display unit displaying the real distance calculated by the calculation unit. The distance calculating apparatus can conveniently and accurately obtain the real distance by only inputting a reduced scale of a map and moving the apparatus along a path connecting two points on the map.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority based on International PatentApplication No. PCT/KR2004/001118, entitled “Distance Calculation Deviceby Ki-Suk KIM, which claims priority of Korean Application No.10-2003-0030479, filed on May 14, 2003.

TECHNICAL FIELD

The present invention relates to a distance calculating apparatus, andmore particularly to a distance calculating apparatus including adisplay window displaying a real distance corresponding to an arbitrarypath between two points on a map, when a reduced scale of the map isinput to the apparatus and the apparatus is moved along the arbitrarypath connecting the two points on the map.

BACKGROUND ART

In general, maps are figures in which a part or all of the earth'ssurface is expressed on a plane with a reduced scale, and seas,mountains, streams, land, etc. are expressed using various symbols,characters, colors, etc. Examples of the maps include topographicalmaps, land registration maps, etc. The reduced scale is a ratio of adistance on a map with respect to a real distance corresponding to thedistance on the map. For example, the reduced scale can be expressed asof 1:100,000 or 1/100,000, which means that a real distance isrepresented on a map by a distance equal to 1/100,000 of the realdistance. The reduced scale can be different depending upon the map usedand is generally displayed at an upper or lower end of the map. Theaccuracy of a map is proportional to the reduced scale of the map.

Maps can be used for various purposes such as searching for paths ordesired places, observing topographies, calculating areas of regions,etc. Among the various purposes, maps are frequently used forcalculating a distance of a road connecting two real positions or adirect distance between two positions. That is, maps are used forcalculating a distance that must be traveled to get from a position toanother position.

Conventionally, troublesome procedures must be performed to obtain areal distance of a real path connecting two real positions using a map.That is, in order to obtain a real distance of a real path, first, afirst point and a second point corresponding to the two real positionsare chosen. Then, when the map path connecting the first point and thesecond point is linear, the map distance can be obtained using a ruler.When the map path connecting the first point and the second point iscurved, the map distance can be obtained by attaching a wet thread tothe map along the map path, detaching the wet thread from the map,stretching the wet thread straight, and then measuring the length of thewet thread corresponding to the map path using a ruler. The map distancemay also be obtained using an opisometer. The real distance iscalculated by multiplying the obtained map distance by the reduced scaledisplayed on the map.

Even when using the opisometer, it is very inconvenient to obtain thereal distance using the above method, and it may be impossible to obtaina real distance corresponding to a continuously curved path using theabove method.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram schematically illustrating a distance calculatingapparatus according to a first embodiment of the present invention;

FIG. 2 is a map exemplified for explaining usage of the distancecalculating apparatus shown in FIG. 1;

FIG. 3 is a flowchart illustrating operation of a calculation unit ofthe distance calculating apparatus shown in FIG. 1;

FIG. 4 is a diagram schematically illustrating a distance calculatingapparatus according to a second embodiment of the present invention; and

FIG. 5 is a diagram schematically illustrating a distance calculatingapparatus according to a third embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Technical Goal of the Invention

The present invention provides a distance calculating apparatus capableof displaying a real distance in a display unit by only inputting areduced scale of a map and moving the apparatus along a map pathcorresponding to a real path of which a real distance is to becalculated.

Disclosure of the Invention

According to an aspect of the present invention, there is provided adistance calculating apparatus calculating a real distance from a mapdistance of a map path connecting a first point and a second point on amap, the apparatus comprising: a housing; a scale input unit into whicha reduced scale is input, disposed in the housing; an optical sensorunit disposed in the housing, the optical sensor unit sensing movementof the housing using light and outputting an electrical signal when thehousing is moved along the map path; a calculation unit disposed in thehousing, the calculation unit calculating the map distance using theelectrical signal input from the optical sensor unit and calculating thereal distance using the map distance and the reduced scale input fromthe scale input unit; and a display unit disposed in the housing, thedisplay unit displaying the real distance calculated by the calculationunit.

The optical sensor unit may comprise: a light emitter emitting light; alight receiver sensing light reflected after being emitted from thelight emitter; and a conversion and output unit converting variations inthe light sensed by the light receiver into an electrical signal andoutputting the electrical signal when the housing is moved.

The housing may have a pen shape, the light emitter may be provided atthe lower portion of the housing, and the light emitted from the lightemitter may be incident on and reflected from the map.

The distance calculating apparatus may further comprise a rolling ballrotatably coupled to the lower end of the housing such that the housingcan roll over a surface of the map while being in contact with thesurface of the map when moving the housing along the map path, and thehousing may have a pen shape.

The light emitter may be disposed inside the housing and the lightemitted from the light emitter may be incident on and reflected from therolling ball.

A lattice shaped pattern may be formed on a surface of the rolling ballsuch that the light receiver easily senses the variations in the lightreflected from the rolling ball as the rolling ball rotates.

The housing may further comprise an input button unit indicating inputto the calculation unit that the housing is positioned at the firstpoint or the second point on the map.

Effect of the Invention

As described above, the distance calculating apparatus according to thepresent invention can conveniently and accurately obtain a real distancebetween two points by only inputting a reduced scale of a map and movingthe distance calculating apparatus along a path connecting the twopoints on the map.

EMBODIMENTS

Hereinafter, exemplary embodiments of the present invention will bedescribed in detail with reference to the attached drawings.

FIG. 1 is a perspective view illustrating a distance calculatingapparatus according to an embodiment of the present invention of which apart is cut off and FIG. 2 is a map exemplified for explaining usage ofthe distance calculating apparatus shown in FIG. 1.

Referring to FIGS. 1 and 2, the distance calculating apparatus 1according to the present embodiment is used to calculate a real distancefrom a map distance, which is a length of a map path MP connecting afirst point A to a second point B, and comprises a housing 10, a scaleinput unit 20, an optical sensor unit 30, a calculation unit 40, adisplay unit 50, and an input button unit 60.

The housing 10 encases most of the components of the distancecalculating apparatus 1 and other components are fitted thereto. Thehousing 10 can have a pen shape and comprises a power source unit 11, anon/off switch 12, a penclip 13, and a rolling ball 15.

The power source unit 11 is disposed inside the upper end portion of thehousing 10 and supplies power required for operation of othercomponents. A battery having a small volume can be used as the powersource unit 11.

The on/off switch 12 can be disposed at the upper end portion of thehousing and controls the flow of current to other components from thepower source unit 11. The on/off switch 12 may be a push type switchwhich alternatively allows current to flow and prevents current fromflowing when pressed.

The penclip 13 is disposed at the upper portion of the housing 10 andallows the distance calculating apparatus 1 to be conveniently attachedto clothes or a map.

The rolling ball 15 is rotatably coupled to the lower end portion of thehousing 10. Therefore, when a user grasps a body of the housing 10,brings the rolling ball 15 into contact with the surface of the map, andthen moves the housing 10 along the map path, the rolling ball 15 rollsalong the map path without slipping due to a frictional force betweenthe rolling ball 15 and the surface of the map.

The rolling ball 15 has a lattice-shaped pattern 17. The lattice-shapedpattern 17 and a non-lattice pattern portion of the rolling ball 15 haveat least one optical characteristic different from each other, forexample, in reflectance, reflecting angle, degree of diffusion, etc.

A reduced scale S of the map of which a distance is to be measured isinput via the scale input unit 20 using various methods of inputtingnumerals. For example, although not shown, the scale input unit 20 mayinclude an input button unit, a selection button unit, and a scaledisplay. In this case, the reduced scale S is input by pressing numeralbuttons on a numeral plate of the input button unit, and the input ofthe reduced scale S is completed by pressing the selection button unit.At this time, the numeral buttons pressed may be displayed in the scaledisplay.

The optical sensor unit 30 is disposed inside of the lower portion ofthe housing 10 and comprises a light emitter 32, a light receiver 34,and a conversion and output unit 36. When the housing 10 is moved alongthe map path, the optical sensor unit 30 senses the movement of thehousing 10 using light and outputs an electrical signal corresponding toa distance of the sensed movement.

The light emitter 32 emits light by means of power supplied from thepower source unit 11. The light emitter 32 may be a light emitting diodebecause a light emitting diode has small power consumption and highlight intensity. In the present embodiment, the light emitted from thelight emitter 32 is incident on and reflected from the rolling ball 15disposed at the lower end portion of the housing 10.

The light receiver 34 senses the light emitted from the light emitter 32and reflected from the rolling ball 15. Since the lattice-shaped pattern17 has the varying light reflecting characteristics, the variations inthe light reflected from the rolling ball 15 can be easily sensed by thelight receiver 34 when the rolling ball 15 rolls.

The conversion and output unit 36 converts the variations in the lightsensed by the light receiver 34 into an electrical signal and outputsthe electrical signal. That is, when the rolling ball 15 of the housing10 is moved along the map path and rotated, the light emitted from thelight emitter 32 and reflected from the rolling ball 15 having thelattice-shaped pattern 17 continuously varies and the conversion andoutput unit 32 converts the variations in the light sensed by the lightreceiver 34 into an electrical signal and then outputs the electricalsignal.

Since the arrangements of specific electrical circuits, etc. for sensingthe variations of light or converting the variations of light into anelectrical signal and outputting the electrical signal can be formedwith well-known specific circuit diagrams and electronic components ofthe electrical circuits will not be presented.

The calculation unit 40 is disposed inside the housing 10 and calculatsthe real distance using the electrical signal input from the conversionand output unit 36 of the optical sensor unit 30 and the reduced scaleinput from the scale input unit 20.

The calculation algorithm of the calculation unit 40 will be describedwith reference to FIG. 3. First, the reduced scale S of a map is inputand stored in advance (first operation), the map distance over which therolling ball 15 rolls on the map is obtained using the electrical signalinput from the conversion and output unit 36 of the optical sensor unit30 (second operation), the real distance is calculated by multiplyingthe map distance by the reduced scale S (third operation), and then thecalculated real distance is output to the display unit described later(fourth operation).

The specific construction of the electrical circuit that performs thecalculation function can be embodied using a well-known technology, andthus a description thereof will be omitted.

The display unit 50 is disposed inside the housing 10 and displays thereal distance calculated by the calculation unit 40, so that a user canread the real distance with his naked eyes.

The input button unit 60 is disposed inside the housing 10 and inputs asignal to the calculation unit 40 indicating that the rolling ball 15 ofthe housing 10 is positioned at the first point A or the second point B.

Usage and advantages of the distance calculating apparatus 1 accordingto the present embodiment will now be described.

First, the on/off switch 12 on the housing 10 of the distancecalculating apparatus 1 is turned on. Then, the light emitter 32supplied with power emits light. At this time, the power is supplied tothe calculation unit 40 as well as the display unit 50, the scale inputunit 20, etc. via the calculation unit 40.

Referring to FIG. 2, after a user grasps the body of the housing 10 andplaces the rolling ball 15 on the first point A, the input button unit60 is pressed to indicate to the calculation unit 40 that the presentposition of the rolling ball 15 is the first point A.

Thereafter, the housing 10 is moved along the map path MP such that therolling ball 15 rolls. When the rolling ball 15 rolls and the housing 10is moved, the light incident on the rolling ball 15 from the lightemitter 32 and sensed by the light receiver 34 varies as the rollingball 15 rotates inside the housing 10. The variation in the light sensedby the light receiver 34 is converted into an electrical signal that isoutput to the calculation unit 40. The housing 10 is moved to the secondpoint B, and the rolling ball 15 rolls without slipping. Then, when therolling ball 15 reaches the second point B, the input button unit 60 ispressed to indicate to the calculation unit 40 that the present positionof the housing 10 is the second point B. Then, the calculation unit 40recognizes the second point B and calculates a distance over which therolling ball has rolled from the first point A to the second point B.

Finally, as described above, the calculation unit 40 calculates the realdistance using the input reduced scale S and the rolling distance (mapdistance) of the rolling ball 15 and outputs the real distance to thedisplay unit 50, and the real distance is displayed in the display unit50. The unit of numerals to be displayed in the display unit 50 may beset to kilometres (Km).

The distance calculating apparatus 1 of the present embodiment canconveniently display the real distance between two points in the displayunit 50, by only inputting the reduced scale S of a map and simplymoving the pen-shaped housing 10 along the map path MP connecting thetwo points on the map. Further, it is possible to conveniently obtain alength of a second path by turning off and then turning on again thedistance calculating apparatus 1 using the on/off switch 12 and movingthe rolling ball 15 over the second path between the first point A andthe second point B, and thus compare the two distances. On the otherhand, the distance measuring apparatus 1 may comprise a reset button.

Since the housing 10 has a pen shape, it is possible to convenientlytransport the distance calculating apparatus 1 when not using thedistance calculating apparatus 1 and to simply and conveniently performmeasurements with the distance calculating apparatus 1.

Since the rolling ball 15 is disposed at the lower end of the housing10, it is possible to easily move the distance calculating apparatus 1along the map path.

Furthermore, since the lattice-shaped pattern 17 is formed on therolling ball 15, the light receiver 34 can easily sense the variationsin the reflected light.

Although the lattice-shaped pattern 17 is formed on the rolling ball 15in the present embodiment, the present invention is not limited to this,and the pattern may have a dense dot shape.

Further, although the input button unit 60 is included in the presentembodiment, the present invention is not limited to this, and anothermethod of indicating to the calculation unit 40 that the pen is over thefirst point A and the second point B may be used.

FIG. 4 shows a distance calculating apparatus 1 a according to anotherembodiment of the present invention.

The distance calculating apparatus 1 a according to the secondembodiment is different from the distance calculating apparatus 1according to the first embodiment in that the distance calculatingapparatus 1 a according to the second embodiment does not comprise therolling ball 15. That is, the light emitted from the light emitter 32 isreflected from the map, not the rolling ball 15. The light is incidenton and reflected from the map through an opening 16 formed in the lowerend portion of the housing 10, and is then sensed by the light receiver34. In order to effectively focus the reflected light on the lightreceiver 34, the distance calculating apparatus may comprise a focusinglens 33. In this case, the housing 10 is stood vertically with the lowerend portion of the housing 10 contacting the map when moved along themap path MP.

The distance calculating apparatus 1 a according to the secondembodiment can attain the same advantages as the distance calculatingapparatus 1 according to the first embodiment other than the advantagedue to the rolling ball 15. In the case of the apparatus 1 a, changingoptical characteristics of the map itself, rather than those of arolling ball, are detected and used to measure distance.

FIG. 5 shows a distance calculating apparatus 1 b according to anotherembodiment of the present invention.

The distance calculating apparatus 1 b according to the third embodimentis different from the distance calculating apparatus 1 according to thefirst embodiment in that an optical sensor unit 30 b of the thirdembodiment is disposed outside the housing 10 and a pattern 17 is notformed on a rolling ball 15 b. Except for these differences, thedistance calculating apparatus 1 b according to the third embodiment isequivalent the distance calculating apparatus 1 according to the firstembodiment.

That is, a light emitter 32 b, a light receiver 34 b, and a conversionand output unit 36 b of the optical sensor unit 30 b are disposedoutside the lower end portion of the housing 10. The light emitted fromthe light emitter 32 b is reflected from the map, not from the rollingball 15 b, and is sensed by the light receiver 34 b disposed outside thehousing 10. The operation and function of the conversion and output unit36 b are equivalent to those of the first embodiment.

On the other hand, the rolling ball 15 b not having the pattern 17serves as a guide allowing the housing 10 to be smoothly moved along themap path MP. The housing 10 can be stood vertically on the map with thelower end portion of the housing 10 contacting the map when moved alongthe map path MP.

The distance calculating apparatus 1 b according to the third embodimentcan attain the same advantages as the distance calculating apparatus 1according to the first embodiment other than the advantage due to thepattern 17.

As described above, the distance calculating apparatus according to thepresent invention can conveniently and accurately obtain a real distancebetween two points by only inputting a reduced scale of a map and movingthe distance calculating apparatus along a path connecting the twopoints on the map.

1. A distance calculating apparatus calculating a real distance from amap distance of a map path connecting a first point and a second pointon a map, the apparatus comprising: a housing; a scale input unit intowhich a reduced scale is input, disposed in the housing; an opticalsensor unit disposed in the housing, the optical sensor unit sensing amovement of the housing using light and outputting an electrical signalwhen the housing is moved along the map path; a calculation unitdisposed in the housing, the calculation unit calculating the mapdistance using the electrical signal input from the optical sensor unitand calculating the real distance using the map distance and the reducedscale input from the scale input unit; and a display unit disposed inthe housing, the display unit displaying the real distance calculated bythe calculation unit, wherein the optical sensor unit comprises; a lightemitter emitting light; a light receiver sensing light reflected afterbeing emitted from the light emitter; and a conversion and output unitconverting variations in the light sensed by the light receiver into anelectrical signal and outputting the electrical signal when the housingis moved, wherein the housing has a pen shape, and the light emitter isdisposed at the lower portion of the housing, and the light emitted fromthe light emitter is incident on and reflected from the map.
 2. Thedistance calculating apparatus according to claim 1, further comprisinga rolling ball rotatably coupled to the lower end of the housing suchthat the housing can roll over a surface of the map while being incontact with the surface of the map when moving the housing along themap path, wherein the housing has a pen shape.
 3. The distancecalculating apparatus according to claim 1, wherein the housing furthercomprises an input button unit indicating to the calculation unit thatthe housing is positioned at the first point or the second point on themap.